High torque reluctance brake device

ABSTRACT

A high torque reluctance brake device for fitness equipment, comprising: an external rotor including a flywheel and an outer ring body; at least two magnetic resistance mechanisms, each of them has a brake field core, a magnetic coil; a support frame for arranging magnetic resistance mechanisms to form an angle larger than 30 degree and to make between the outer periphery of the brake field core and the outer ring body has a gap; the control circuit unit transmits suitable current to the magnetic coil, then between the brake field core and the magnetic ring produced a eddy current magnetic resistance and forms a reverse resistance to the external rotor. By choosing different resistance setting can increase the variability of exercise and improve the comfort of exercise.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention relates to a fitness equipment, especially to one that hasa high torque reluctance brake device having a control circuit forproviding corresponding current according to required torque value tomake the rotated flywheel that coupled to the magnetic resistancemechanism with predetermined angle produces a reverse resistance.

2. Description of the Related Art

The flywheel is widely used in many fitness equipment for providingexercise load by the inertia of rotation; FIG. 1A illustrated a U.S.Pat. No. 5,711,404 a magnetic adjustable loading device with eddycurrent, the device including: a rotor compose of a flywheel 710 and ametal conductor 720; a stator 750 composed of iron sheet 751 andpermanent magnet 752 is arranged at the inner periphery, by the leadingof the adjustment device 771 makes the iron sheet 751 displaced andfurther change the gap dl between the rotor 710,720 and the stator 750,so the magnetic flux density is changed to achieve the effect ofstepless continuous adjustment of load resistance; However, theadjustment device 771 is manually controlled and cannot achieve theeffect of automatic adjustment of load, so this patent has thedisadvantage of lack of automatic adjustment.

In recent years, fitness equipment often uses flywheels installed withpermanent magnets, and then use armatures as stators to make statorcoils generate current to be the power that provided for the control andthe brake load; FIG. 1B illustrated a U.S. Pat. No. 6,084,325 a brakedevice with a combination of power-generating and eddy-current magneticresistance, the device including: a flywheel 820 rotated by the rotatewheel, the flywheel 820 is stuck to a permanent magnet 821 and statorcore 830 to form a magnetic circuit, and further make the coil 831generate current; the current is rectified and filtered into DC forproviding power to the control panel and brake field core 850, makingthe brake field core 850 generate a eddy current and further causes areluctance effect to flywheel 820; this kind of structure can achieveexcellent sports effects, and the output power of the generator isclosely related to the speed, since the speed of the generator islimited by the magnetic resistance, it has not performed its dueefficiency; moreover, the mechanism is more complicated and themanufacturing cost is higher, so it is not suitable for installation onsmall or less control functions fitness equipment.

SUMMARY OF THE INVENTION

It is a primary objective of the present invention to provide an eddycurrent reluctance brake device having the function of automaticadjustment that can be applied on small fitness equipment.

It is another objective of the present invention to provide a hightorque reluctance brake device that can reduce the manufacturing costand improve the load efficiency.

It is another objective of the present invention to provide a hightorque reluctance brake device that has a transmission port for loadingthe resistance curve diagram in order to increase the variability ofexercise and improve the comfort of exercise.

In order to achieve the above objectives, the present inventionincluding: a support frame, a rotate shaft, an external rotor, at leasttwo magnetic resistance mechanism, and a control circuit unit; whereinthe support frame having a front frame body and a rear frame body fixedby multiple positioning rod, and the support frame having a fixing basefor fixing on the frame of the fitness equipment; the rotate shaftpivoted in a shaft hole of the support frame; the transmission wheelpivoted on the rotate shaft and located on the outer side of the supportframe for receiving the power transmitted by fitness equipment; theexternal rotor including a flywheel and a magnetic ring, the flywheelhas a wheel nave arranged at the center, and the wheel nave has a shafthole for setting the wheel nave on the rotate shaft, the magnetic ringhas high magnetic flux density and arranged closely on the outerperiphery of an outer ring body of the flywheel, and the transmissionwheel drives the external rotor to rotate; the magnetic resistancemechanisms, each of them has a brake field core, a magnetic coil, aninput wire connected to the magnetic coil, a front bracket, and a rearbracket, the brake field core has a containing space for arranged themagnetic coil, the front bracket and the rear bracket fix the brakefield core at the positioning hole of the front and rear frame body, themagnetic resistance mechanisms are arranged at the outer periphery ofthe magnetic ring and form an angle greater than 30 degrees and lessthan 180 degrees between each other, and between the outer periphery ofthe brake field core and the magnetic ring has a magnetic field gap; thecontrol circuit unit installed on the side of the support frame in abuilt-in form, the control circuit unit has at least a micro processer,a DC control circuit, an input device for inputting required torquevalue, and a transmission port for loading the resistance curve diagram,the control circuit is connected to a direct current and electricallyconnected to the input wire of the magnetic coil.

Whereby the micro processer produces a control signal to the DC controlcircuit after calculating the required torque value and further providesa suitable current transmitted to the magnetic coil of the magneticresistance mechanisms, and the current of the magnetic coil willgenerate a magnetic field on the brake field core through the principleof electromagnetic induction, then a closed magnetic circuit is formedbetween the magnetic field and the coupled rotated magnetic ring; sincethe external rotor is rotating, the closed magnetic circuit will bedestroyed, according to Lenz's law, when a stable magnetic circuit isdestroyed by external force, a reverse resistance of the same magnitudewill be produced to resist so as to achieve the effect of providing anexercise load, and by choosing resistance curve diagram can increase thevariability of exercise and improve the comfort of exercise.

Also, the included angle of the two magnetic resistance mechanisms islarger than 30 degree and smaller than 90 degree.

Also, the transmission wheel is a belt pulley.

With the features disclosed above, the present invention, high torquereluctance brake device, has below benefits:

1. The present invention has the transmission wheel that drives theexternal rotor to rotate, and has a flywheel for providing inertiarotation and a magnetic ring having high magnetic flux density; themagnetic resistance mechanisms have a brake field core, a magnetic coil,and a magnetic field gap is between the outer periphery of the brakefield core and the magnetic ring, in order to produce reluctance effect;The present invention has an input device for inputting the torquevalue, and the DC control circuit will generate a suitable currentaccordingly to the magnetic coil to form the required exerciseresistance; Since the stator coil and AC/DC conversion componentsrequired for power generation are not arranged in the present invention,it can simplify the mechanism, reduce the volume, and reduce themanufacturing cost, and it can be applied to small fitness equipment;The present invention controls the reluctance load by the magnitude ofthe current applied to the magnetic coil. Since the mechanism is anon-contact resistance device, the present invention also has theadvantages of easy control of resistance, no wear of components, and lowmaintenance cost.

2. The external rotor of the present invention includes a flywheel forproviding inertia rotation and a magnetic ring having high magnetic fluxdensity, and the magnetic ring arranged closely on the outer peripheryof an outer ring body of the flywheel, and the transmission wheel drivesthe external rotor to rotate; two magnetic resistance mechanismsarranged at the outer periphery of the magnetic ring, and between theouter periphery of the brake field core and the magnetic ring has amagnetic field gap; since a suitable current is transmitted to themagnetic coil of the magnetic resistance mechanisms, and the current ofthe magnetic coil will generate a magnetic field on the brake fieldcore, according to Lenz's law, the magnetic field will give a reverseresistance of the same magnitude to the magnetic ring; since themagnetic ring having high magnetic flux density and the magneticresistance mechanisms are arranged at the outer periphery of themagnetic ring and form an angle greater than 30 degrees and less than180 degree, than the magnetic lines of the brake field core will notinterfere with each other, and the eddy current reluctance will reachthe highest torque, so the present invention can achieve the effect ofhigh-efficiency exercise loads.

3. The present invention includes an input device for inputting requiredtorque value, and a transmission port for loading the resistance curvediagram; After the user key in the required torque value, the microprocesser of the control circuit unit calculates the required torquevalue and the resistance curve diagram, the micro processer furtherprovides a suitable current transmitted to the magnetic coil of themagnetic resistance mechanisms, then between the brake field core andthe magnetic ring produced a eddy current magnetic resistance and formsa reverse resistance to the external rotor. Because the resistance curvediagram allows the user to feel the smooth resistance of differentdifficulties, it can not only improve the comfort but also avoid theinjury caused by the sudden resistance change. Therefore, by choosingdifferent resistance curve diagram can increase the variability ofexercise and improve the comfort of exercise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic diagram illustrating structure of magneticadjustable loading device with eddy current according to the prior art;

FIG. 1B is a schematic diagram illustrating structure of brake devicewith a combination of power-generating and eddy-current magneticresistance according to the prior art;

FIG. 2 is an exploded perspective view of the present invention;

FIG. 3 is an assembly perspective front views of the first embodiment ofthe present invention;

FIG. 4 is an assembly perspective rear view of the first embodiment ofthe present invention;

FIG. 5 is an assembly front views of the first embodiment of the presentinvention;

FIG. 6 is an assembly sectional views of the present invention;

FIG. 7 is a perspective rear view of the external rotor of the presentinvention;

FIG. 8 is a schematic diagram illustrating structure of the presentinvention in the first embodiment;

FIG. 9 is a schematic diagram illustrating the loading of the resistancecurve diagram of the present invention;

FIG. 10 is an assembly perspective views of the second embodiment of thepresent invention;

FIG. 11 is an assembly front views of the second embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For better understanding of present invention, I provide the embodimentand drawing enclosed for detailed description. Those who skilled in theart can understand purpose, the feature and benefit of the presentinvention from the contents disclosed in this specification. Kindlynoted that the present invention can be implemented or applied throughother different specific embodiments and based on different viewpointsvarious details in this specification can be various changed withoutdeparting from the spirit of the present invention. In addition, thedrawings attached to the present invention are merely a schematicillustration and they are not depicted in actual dimensions. Thefollowing embodiments will further describe the related technicalcontent of the present invention in detail, but the disclosed content isnot intended to limit the technical scope of the present invention

Referring to FIG. 2, the high torque reluctance brake device for fitnessequipment 100 comprising: a support frame 10 formed by a front framebody 11 and a rear frame body 12, the upper end of the front frame body11 and the rear frame body 12 have a shaft hole 13, around the shafthole 13 has multiple positioning holes 14 arranged with equal space, thelower end of the front frame body 11 and the rear frame body 12 have afixing base 15, and by locking the bolt with fixing slot 16 fixes thesupport frame 10 on the fitness equipment; multiple positioning rods 17fixed by screw nuts inside the multiple positioning holes 14, making thefront frame body 11 and the rear frame body 12 combine as one; anexternal rotor 20 including a flywheel 21 and a magnetic ring 22, theflywheel 21 is an inertia rotate disc having an outer ring body 211 andan outer ring body 212, and the center of the outer ring body 212 has awheel nave 214 with a shaft hole 213; a rotate shaft 30 set through theshaft hole 213 and engaged with a connect key 215 to make the rotateshaft 30 and flywheel 21 rotated simultaneously; a transmission wheel 40arranged by a one-way bearing 31 on one ends of the rotate shaft 30 forreceiving the power transmitted by fitness equipment in one direction,and the transmission wheel 40 of the present invention is a belt pulley;the rotate shaft 30 is arranged at the both side of the flywheel 21 andthe wheel nave 214, each of them has a ball-bearing 32, around theball-bearing 32 has a bearing housing 33, the front and rear ends of thebearing housing 33 is locked inside the shaft hole 13 of the front framebody 11 and rear frame body 12.

Also, at least two magnetic resistance mechanisms 50, each of them has abrake field core 51, a magnetic coil 52, an input wire 53 connected tothe magnetic coil 52, a front bracket 54, and a rear bracket 55, thebrake field core 51 has a containing space for arranged the magneticcoil 52; the front bracket 54 and the rear bracket 55 are arranged atthe both side of the brake field core 51, and set through the brakefield core 51 by a bolt, then fix the brake field core 51 at thepositioning hole 14 of the front 54 and rear frame body 55;

For avoiding the magnetic field lines of the brake field core 51 of twomagnetic resistance mechanisms 50 interfere with each other and make theeddy current magnetic resistance reach the highest torque, whilearranging the two magnetic resistance mechanisms 50 at the outerperiphery of the magnetic ring 22, the arranged angle θ has to begreater than 30 degrees and less than 180 degrees between each other;Also, for providing reluctance effect, while arranging the brake fieldcore 51 of the front bracket 54 and the rear bracket 55, between theouter periphery of the brake field core 51 and the magnetic ring 22require a magnetic field gap G; the arranged angle θ of the two magneticresistance mechanisms 50 in first embodiment is greater than 30 degreesand less than 90 degrees, as FIGS. 3-6 showing; the arranged angle θ ofthe two magnetic resistance mechanisms 50 in second embodiment isgreater than 30 degrees and less than 180 degrees, as FIGS. 10-11showing; the limitation of arranging angle θ greater the 30 degrees notonly avoid the magnetic field lines of the brake field core 51 of twomagnetic resistance mechanisms 50 interfere with each other, but alsomake the rotation of the external rotor 20 produces a smaller yaw andincreases its service life, because under the premise of producing thesame torque, the two magnetic resistance mechanisms 50 can disperse thereluctance effect on two parts of the outer periphery of the magneticring 22, compared with only one magnetic resistance mechanism 50, thereluctance effect can only be concentrated on the outer periphery of themagnetic ring 22.

FIG. 7 is showing the structure of the external rotor 20; the externalrotor 20 has a flywheel 21 and a magnetic ring 22; the flywheel 21 hasan outer ring body 211 and an inner ring body 212, and at the center ofthe inner ring body 212 has a wheel nave 214 with a shaft hole 213; theshaft hole 213 has a key slot 216, when the shaft hole 213 is arrangedon the rotate shaft 30, a connect key 215 is engaged with the key slot216, making the rotate shaft 30 and the flywheel 21 rotatesimultaneously; the magnetic ring 22 is made of material which havinghigh magnetic flux density, in the present invention the magnetic ring22 is made of carbon steel with carbon content 0.15˜0.25%; moreover, themagnetic ring 22 is closely arranged at the outer periphery of the outerring body 211 of the flywheel 21, or directly formed on the outerperiphery of the outer ring body 211, by the magnetic permeability ofthe magnetic coil 52 create a closed magnetic circuit; the reasonarranging the magnetic ring 22 at the outer periphery of the outer ringbody 211 is to increase the magnetic flux density of the external rotor20, and make the brake field core 51 of the magnetic resistancemechanism 50 create a larger eddy current magnetic resistance with outcausing extra producing cost; But the material of the magnetic ring 22and the arrangement of the magnetic ring 22 of the present invention isnot limited to such application.

FIG. 8 is illustrating the arrangement of the first embodiment of thepresent invention, including: a control circuit unit 60 installed on theside of the support frame 10 in a built-in form, the control circuitunit 60 has at least a micro processer 61, a DC control circuit 62, aninput device 63 for inputting required torque value, and a transmissionport 64 for loading the resistance curve diagram; the exercise forceapplied by the user drives the transmission mechanism A of the fitnessequipment that linked to the transmission wheel 40 to make the externalrotor rotate 20. After the user inputs the desired torque value of theexercise by the input device 63 and selects the desired resistance curveby the transmission port 64, the microprocessor 61 refers to thetrajectory of the resistance curve and the torque setting value, andthen sends the correct signal to the DC control circuit 62 for providinga suitable current transmitted to the input wire 53 of the magneticresistance mechanisms 50, and the current of the magnetic coil 52 willgenerate a magnetic field on the brake field core 51 through theprinciple of electromagnetic induction, then a closed magnetic circuitis formed between the magnetic field and the coupled rotated magneticring 22; since the external rotor 20 is rotating, the closed magneticcircuit will be destroyed, according to Lenz's law, when a stablemagnetic circuit is destroyed by external force, a reverse resistance ofthe same magnitude will be produced to resist so as to achieve theeffect of providing an exercise load, and the microprocessor 61 keepsrefer to torque value setting and control the current of the magneticcoil 52 by the DC control circuit 62 for making the reluctance equal tothe torque value that user inputted, so as to achieve the effect ofhaving required exercise load.

Referring to FIG. 9, a schematic diagram of the resistance curve of theexercise, the resistance curve has many graphs of different difficulty.Basically its resistance is set to the initial stage, the gradualincrease stage, and the torque control stage; when the input current isunchanged at the initial stage, the input current of the gradualincrease stage will increase its resistance linearly, and the inputcurrent will be automatically adjusted according to the torque settingconditions at the torque control stage; Because the resistance curvediagram allows the user to feel the smooth resistance of differentdifficulties, it can not only improve the comfort but also avoid theinjury caused by the sudden resistance change. Therefore, by choosingdifferent resistance curve diagram can increase the variability ofexercise and improve the comfort of exercise.

The external rotor 20 of the present invention is drove by thetransmission wheel 40 and rotate, including a flywheel 21 for providinginertia rotation and a magnetic ring 22 having high magnetic fluxdensity; two magnetic resistance mechanisms 50 arranged at the outerperiphery of the magnetic ring 22, and between the outer periphery ofthe brake field core 51 and the magnetic ring 52 has a magnetic fieldgap G for providing reluctance; the present invention has a input device63 for inputting desired torque, and the DC control circuit 62 willprovide a suitable current to the magnetic coil 52 for generatingexercise load; Since the stator coil and AC/DC conversion componentsrequired for power generation are not arranged in the present invention,it can simplify the mechanism, reduce the volume, and reduce themanufacturing cost, and it can be applied to small fitness equipment;The present invention controls the reluctance load by the magnitude ofthe current applied to the magnetic coil 52. Since the mechanism is anon-contact resistance device, the present invention also has theadvantages of easy control of resistance, no wear of components, and lowmaintenance cost.

Also, the external rotor 20 of the present invention includes a flywheel21 for providing inertia rotation and a magnetic ring 22 having highmagnetic flux density, and the magnetic ring 22 arranged closely on theouter periphery of the flywheel 21, and the transmission wheel 40 drivesthe external rotor 20 to rotate; two magnetic resistance mechanisms 50arranged at the outer periphery of the magnetic ring 22, and between theouter periphery of the brake field core 51 and the magnetic ring 22 hasa magnetic field gap G; since a suitable current is transmitted to themagnetic coil 52 of the magnetic resistance mechanisms 50, and thecurrent of the magnetic coil 52 will generate a magnetic field on thebrake field core 51, according to Lenz's law, the magnetic field willgive a reverse resistance of the same magnitude to the magnetic ring 22;since the magnetic ring 22 having high magnetic flux density and themagnetic resistance mechanisms 50 are arranged at the outer periphery ofthe magnetic ring 22 and form an angle greater than 30 degrees and lessthan 180 degree, than the magnetic lines of the brake field core 51 willnot interfere with each other, and the eddy current reluctance willreach the highest torque, so the present invention can achieve theeffect of high-efficiency exercise loads.

Also, the present invention includes an input device 63 for inputtingrequired torque value, and a transmission port 64 for loading theresistance curve diagram; After the user key in the required torquevalue, the micro processer 61 of the control circuit unit 60 calculatesthe required torque value and the resistance curve diagram, the microprocesser 61 further provides a suitable current transmitted to themagnetic coil 52 of the magnetic resistance mechanisms 50, then betweenthe brake field core 51 and the magnetic ring 22 produced a eddy currentmagnetic resistance and forms a reverse resistance to the external rotor20. Because the resistance curve diagram allows the user to feel thesmooth resistance of different difficulties, it can not only improve thecomfort but also avoid the injury caused by the sudden resistancechange. Therefore, by choosing different resistance curve diagram canincrease the variability of exercise and improve the comfort ofexercise.

What is claimed is:
 1. A reluctance brake device for fitness equipment,comprising: a support frame having a front frame body and a rear framebody fixed by multiple positioning rods, and the support frame having afixing base for fixing on the frame of the fitness equipment, the frontframe body and a rear frame body each having at least a pair ofpositioning holes; a rotate shaft pivoted in a shaft hole of the supportframe; a transmission wheel pivoted on the rotate shaft and located onan axially outer side of the support frame for receiving powertransmitted by the fitness equipment; an external rotor including aflywheel and a magnetic ring, the flywheel has a wheel nave arranged ata center and the wheel nave has a shaft hole for setting the wheel naveon the rotate shaft, the magnetic ring has a certain magnetic fluxdensity and arranged closely on an outer periphery of an outer ring bodyof the flywheel, and the transmission wheel drives the external rotor torotate; at least two magnetic resistance mechanisms, each of themagnetic resistance mechanisms has a brake field core, a magnetic coil,an input wire connected to the magnetic coil, a front bracket, and arear bracket, each of the brake field cores has a containing space forarranging a corresponding one of the magnetic coils, the front bracketand the rear bracket of each of the two magnetic resistance mechanismsfix a corresponding one of the brake field cores at a respective one ofthe positioning holes of the front frame body and rear frame body, themagnetic resistance mechanisms being arranged at an outer periphery ofthe magnetic ring and form an included angle therebetween greater than30 degrees and less than 180 degrees, and a magnetic field gap beingdisposed between an outer periphery of the brake field core and theouter periphery of the magnetic ring; and a control circuit unitinstalled on an axially outer side of the support frame, the controlcircuit unit having at least a micro processer, a DC control circuit, aninput device for inputting a required torque value, and a transmissionport for loading a resistance curve diagram, and the control circuitbeing connected to a source of direct current and electrically connectedto the input wire of the magnetic coil; whereby the micro processercalculates a required torque value and outputs a control signalcorresponding to the required torque value to the DC control circuit,the DC control circuit outputs a current transmitted to the magneticcoils of the magnetic resistance mechanisms responsive to the controlsignal, and the current of the magnetic coils respectively generatemagnetic fields on the brake field cores corresponding thereto to formclosed magnetic circuits between the brake field cores and the magneticring as the magnetic ring rotates along with the external rotor, whereinthe closed magnetic circuit will be interrupted responsive to a stablemagnetic circuit being interrupted by an external force, and a reverseresistance of an equal magnitude will be produced to resist the externalforce.
 2. The reluctance brake device as claimed in claim 1, wherein theincluded angle of the two magnetic resistance mechanisms is larger than30 degrees and smaller than 90 degrees.
 3. The reluctance brake deviceas claimed in claim 1, wherein the included angle of the two magneticresistance mechanisms is larger than 90 degrees and smaller than 180degrees.
 4. The reluctance brake device as claimed in claim 1, whereinthe transmission wheel is a belt pulley.